94 def sha1(s=''):

    94 from hashlib import md5, sha1

    95     '''

    96     Low-overhead wrapper around Python's SHA support

    97 

    98     >>> f = _fastsha1

    99     >>> a = sha1()

   100     >>> a = f()

   101     >>> a.hexdigest()

   102     'da39a3ee5e6b4b0d3255bfef95601890afd80709'

   103     '''

   104 

   105     return _fastsha1(s)

   106 

   107 def _fastsha1(s=''):

   108     # This function will import sha1 from hashlib or sha (whichever is

   109     # available) and overwrite itself with it on the first call.

   110     # Subsequent calls will go directly to the imported function.

   111     if sys.version_info >= (2, 5):

   112         from hashlib import sha1 as _sha1

   113     else:

   114         from sha import sha as _sha1

   115     global _fastsha1, sha1

   116     _fastsha1 = sha1 = _sha1

   117     return _sha1(s)

   118 

   119 def md5(s=''):

   120     try:

   121         from hashlib import md5 as _md5

   122     except ImportError:

   123         from md5 import md5 as _md5

   124     global md5

   125     md5 = _md5

   126     return _md5(s)